It is well known in the prior art that a diversity of commodities are transported by land in railway tank cars, truck trailers, transport tankers, etc. Railway tank cars typically are constructed with a single manway entry disposed atop and at the longitudinal center thereof. Prior to being filled or loaded with a particular commodity, such a tank car must be throughly cleaned or rinsed, depending upon the circumstances, for health and safety reasons. Such cleaning and rinsing operations have heretofore been not only labor-intensive and time-consuming, but also hazardous.
It is also well known in the art that there frequently are stubborn deposits contained on the interior surfaces including the bulkheads and floor of tank cars and the like which necessitate the use of a high pressure fluid spray to dislodge such deposits. Typically, to accurately direct such high pressure fluid spray to successfully dislodge deposits and the like, manual intervention is required. As will, of course, be appreciated by those skilled in the art, having a worker enter a tank car through a manway and then spray the various interior surfaces of the tank car under limited maneuverability and lighting conditions subjects the worker to dangers of skin, eye, nose and throat irritation or poisoning attributable to unknown chemicals and contaminants, suffocation from fumes, and physical injury due to slippery surfaces and foreign obstacles and the like, and even from explosions.
There have been several improvements in the art to provide different varieties of robotic means or similar apparatus to improve the methodology for cleaning and washing the interior surfaces of tank cars and the like. For instance, the instant inventor disclosed a robotic apparatus for cleaning and stripping tank cars and the like in U.S. Pat. Nos. 5,352,298; 5,518,553; 5,720,310; and 6,021,793. While these cleaning devises teach minimal human intervention and have proven to be useful in the marketplace, circumstances arise for which only providing high-pressure hydroblastins or the like at close proximity to the surfaces being cleaned is capable of purgings stubborn, entrenched tank residues or the like. It will be appreciated by those skilled in the art that such intense hydroblasting via "hand-gunning" is inherently difficult to orchestrate remotely through a tank car manway.
As will be understood by those skilled in the art, since tank cars are typically approximately 40 feet long, it is necessary to extend any cleaning head at least 20 feet from the manway in order to accomplish effective cleaning operations in the absence of entry by a human operator. To accomplish such a demanding cleaning task, a cleaning apparatus must be designed to have the inherent ability to fully reach with a high pressure blast-head--from a manway--all of the interior surfaces of a tank car and the like. A cleaning device affording these capabilities has hereinbefore been unknown in the art.
Accordingly, these limitations and disadvantages of the prior art are overcome with the present invention, and improved cleaning means and techniques are provided which are useful for remotely and robotically cleaning and washing the interior surfaces of tank cars and the like.